In 2009 and 2010, the International Criminal Court issued arrest warrants against Mr Bashir for genocide, war crimes, and crimes against humanity related to the conflict in Darfur, which has claimed at least 300,000 lives.

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Media captionTrump's first trip: What's on the agenda in Saudi Arabia?

He denies the charges, and has successfully evaded arrest for several years.

Saudi Arabia is not a signatory to the statute that founded the ICC and neither Sudan nor the US have ratified it.

But a US official told NBC News earlier that the Trump administration opposed invitations or travel by individuals facing ICC indictments.

"While the United States is not a party to the Rome Statute... we nevertheless strongly support efforts to hold accountable those responsible for genocide, crimes against humanity and war crimes," the official said.

The Saudi summit brings together more than 50 leaders from Arab and Muslim nations.

Mr Trump will deliver a speech on his "hopes for a peaceful vision of Islam".